JP2013170638A - Breather device of transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent oil mist from squirting to the outside of a transmission by suppressing inflow of the oil mist into a breather chamber, even when oil in a transmission is biased and oil surface is raised.SOLUTION: On an upper part of a partition wall 8 dividing a transmission case 3 into a front chamber 6a and a rear chamber 7a, a front chamber side breather chamber 13 and a rear chamber side breather chamber 14 are respectively disposed via a partition wall 8, both breather chambers 13, 14 are brought into communication by a breather communication path 18 and the other end of the breather passage 19 of which one end is brought into communication with the outside of the transmission case 3 is brought into communication with the center of the breather passage 18. Further, a ball valve 22 is arranged on the breather communication path 18 and stopper rings 21a, 21b which cause ball valves 22 to abut on both sides of the breather communication path 18 to close a flow path are arranged. When a vehicle performs an acceleration running or deceleration running, the ball valve 22 is moved and oil is biased and the breather chamber 13 or 14 of the side where the oil surface is raised is closed.

Description

  The present invention relates to a breather device for a transmission that prevents the oil from being ejected out of the transmission even if the oil level in the transmission is biased to one side.

  In general, since the internal pressure of a vehicle transmission is likely to fluctuate due to the influence of a temperature change or the like, a breather device that keeps the internal pressure constant is provided. Then, due to the differential pressure between the internal pressure and the atmospheric pressure, the internal pressure is kept constant by injecting the breather gas in the transmission from the breather device to the outside of the transmission when the internal pressure is high, and taking the external air into the interior when the internal pressure is low. I have to.

  Incidentally, since a rotating body such as a gear is rotating in the transmission, oil mist stirred by the rotating body is drifting. Therefore, the oil mist easily flows into the breather chamber together with the breather gas, and the oil mist is easily ejected out of the transmission together with the breather gas.

  For this reason, in many cases, a labyrinth chamber upstream of the breather chamber is provided, and gas-liquid separation is performed when passing through the labyrinth chamber. For example, in Patent Document 1 (Japanese Patent Application Laid-Open No. 10-325456), a labyrinth is formed by an inner wall portion in a breather chamber, and an oil mist passing through the breather chamber is caused to collide with the inner wall portion to form liquid droplets. A technique is disclosed that separates and breathes only the breather gas out of the transmission.

  However, for example, when the breather inlet of the breather chamber is provided in the rear part of the transmission, the oil stored in the transmission is biased toward the rear side of the transmission and the oil level in the rear part rises during uphill traveling or acceleration traveling. Therefore, the amount of oil splashed up by the rotating body increases and oil mist easily flows into the breather chamber. On the other hand, when the breather inlet of the breather chamber is disposed in the front part of the transmission, the oil level rises in the front part of the transmission because the oil is biased and rises during downhill traveling or decelerating traveling, so it jumps by the rotating body. The raised oil will easily flow into the breather chamber.

  In order to cope with this, for example, in Patent Document 2 (Japanese Patent Laid-Open No. 2011-75087), a first movable plate that moves in the vehicle front-rear direction and closes a part of the suction port, and moves in the vehicle width direction are disclosed. A second movable plate that closes a part of the suction port is disposed at the inlet of the breather chamber, and by moving both movable plates, the portion of the suction port that approaches the oil level is closed and moved to the breather chamber. A technique for preventing the inflow of oil is disclosed.

JP-A-10-325456 JP 2011-75087 A

  In the technique disclosed in Patent Document 2 described above, only a part of the suction port is blocked by the movable plate, and in order to effectively prevent the oil from flowing into the breather chamber, the suction port is formed to be large. It is necessary to have a structure in which only a portion far away from the oil surface of the oil is opened by the movement of the movable plate.

  However, there is a limit to forming a large inlet in the transmission. Therefore, by moving the movable plate, it is possible to prevent a certain amount of oil from flowing, but to block the oil from flowing more effectively. This is not possible and oil may be released from the breather chamber to the atmosphere.

  As a result, the technique disclosed in Patent Document 2 described above functions as a substitute for the labyrinth described above, but the oil flowing into the breather chamber is separated from the breather gas, and the breather gas with reduced oil mist is transmitted to the transmission. It is difficult to blow out.

  In view of the above circumstances, the present invention suppresses the inflow of oil mist into the breather chamber even when the oil level in the transmission is biased and the oil level rises, and the oil mist is jetted out of the transmission. It is an object of the present invention to provide a breather device for a transmission that can prevent the above-described problem.

  A breather apparatus for a transmission according to the present invention includes at least two divided cases obtained by dividing a transmission case mounted on a vehicle by a plane orthogonal to a drive shaft disposed in the transmission case, Partition walls that partition between the split cases, oil circulation holes that are provided at positions lower than the oil oil level of the partition walls and communicate between the adjacent split cases, and breather gas in each split case flows A breather chamber having an inlet, and a breather passage for escaping the breather gas that has flowed into the breather chamber to the outside of the transmission case, the breather chamber being provided at an upper portion in each of the divided cases, and the partition wall The breather chambers provided in each of the divided cases adjacent to each other are communicated with each other via a breather communication passage, and the breather communication passage communicates with the breather passage. Is characterized in that the breather switching valve to shut off selectively according the in the communication passage and one with the breather passage of the breather chamber to the deceleration travel or self-weight of the vehicle is interposed.

  According to the present invention, the breather chamber provided in each of the adjacent divided cases via the partition wall communicates with the breather communication passage, and one of each breather chamber and the breather passage are connected to the breather communication passage. A switching valve that selectively shuts off according to the acceleration / deceleration traveling of the vehicle or its own weight is provided, and the switching valve shuts off one of the breather chambers during acceleration traveling and deceleration traveling, or uphill traveling and downhill traveling, and the other breather Since the chamber is communicated with the breather passage, oil mist flows into the breather chamber even when the oil level in the transmission rises and the oil level rises during acceleration / deceleration traveling or uphill / downhill traveling. It is possible to suppress the oil mist from being ejected out of the transmission case.

External view of vertical transmission Schematic cross section of transmission case during flat road cruise Enlarged view of arrow III in FIG. IV-IV sectional view of Fig. 3 Schematic diagram showing the operation of the breather device when traveling on a flat road Schematic diagram showing the operation of the breather device during acceleration running Schematic diagram showing the operation of the breather device during slow running

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the ⊥ in FIG. 2 is a vertical symbol.

  As shown in FIG. 1, the automatic transmission 1 according to the present embodiment is mounted in a front engine room of a vehicle (not shown) with a rear portion slightly inclined downward and extending along the vehicle body longitudinal direction. It is a vertical type. The automatic transmission 1 has a torque converter case 2 connected to an engine (not shown) at a front portion, a transmission case 3 connected to a rear portion thereof, and an extension case 4 connected to a rear portion thereof.

  A torque converter is disposed in the torque converter case 2, and an input shaft 2a of the torque converter is connected to an output shaft (not shown) of the engine.

  As shown in FIG. 2, a drive shaft 5 that is connected to the output shaft 2 b of the torque converter and extends coaxially is disposed in the transmission case 3. The transmission case 3 is a plane perpendicular to the drive shaft 5 and has a body split structure that is divided into a front case 6 and a rear case 7 as two divided cases. A partition wall 8 is formed therebetween. The partition wall 8 is formed integrally with one of the front case 6 and the rear case 7, and the front chamber 6 a in the front case 6 and the rear chamber 7 a in the rear case 7 are partitioned through the partition wall 8. ing. Further, the middle of the drive shaft 5 inserted into the transmission case 3 is rotatably supported by the partition wall 8 via a bearing 9. Further, on the drive shaft 5, gear trains 10a and 10b including a transmission mechanism such as a planetary gear train are divided into a front chamber 6a and a rear chamber 7a.

  Oil reservoirs 6b and 7b are formed at the bottoms of the front chamber 6a and the rear chamber 7a, respectively. These oil reservoirs 6b and 7b are located below the partition wall 8 and below the oil level of the oil. It communicates through an oil circulation hole 8a provided at a low position.

  Furthermore, an oil strainer 11 is exposed to the oil reservoir 6b of the front chamber 6a. The oil strainer 11 is communicated with an oil pump (not shown), and the oil stored in the oil reservoir 6b is sucked up via the oil strainer 11 by driving the oil pump.

  The oil sucked up and pressurized by the oil pump is used as an operating oil pressure of a transmission control device (not shown), and is supplied to lubrication units such as the gear trains 10a and 10b to lubricate and cool them. The oil used for the shift control and lubrication is returned to the oil reservoirs 6b and 7b formed at the bottoms of the front chamber 6a and the rear chamber 7a and circulated. In this case, as shown in FIG. 2, since the oil reservoirs 6b and 7b are communicated with each other through the oil circulation hole 8a, the oil reservoirs 6b are temporarily stopped on a flat road or are cruising. , 7b, the oil level of the oil is maintained almost constant. As described above, since the automatic transmission 1 according to the present embodiment is mounted with the rear portion inclined downward, the drive shaft 5 is inclined downward from the front to the rear with respect to the oil level of the oil. .

  Also, a breather device 12 is provided on the upper part of the partition wall 8. The breather device 12 is disposed substantially in parallel with the drive shaft 5 in the front-rear direction. Therefore, when the automatic transmission 1 is mounted in the rear lower inclined state, the layout of the state inclined rearward and lower is as follows. Become.

  As shown in FIG. 3, in this breather device 12, breather chambers 13 and 14 are respectively formed on the front chamber 6a side and the rear chamber 7a side with the partition wall 8 interposed therebetween. The breather chambers 13 and 14 separate oil mist contained in the breather gas flowing from the front chamber 6a and the rear chamber 7a. As shown in FIG. 4, the rear chamber side breather chamber 14 is a transmission. An arc shape is formed along the inner wall of the case 3 in a direction perpendicular to the drive shaft 5. Also, a breather inlet 14 a is opened on one side of the rear chamber side breather chamber 14. Further, an oil drain passage 14b communicating with the rear chamber 7a is formed at the lowest position of the bottom of the rear chamber side breather chamber 14, and an orifice 15 is provided in the oil drain passage 14b.

  On the other hand, the front chamber side breather chamber 13 is substantially symmetric with the rear chamber side breather chamber 14 described above. The breather inlet 13a is opened on the upper side, and the front chamber 6a side is at the lowest position at the bottom. A communicating oil drain passage 13b is formed, and an orifice 15 is provided in the oil drain passage 13b.

  Further, as shown in FIG. 3, labyrinths 16 and 17 are communicated with the upstream side of the breather inlets 13a and 14a opened at the upper portions of the breather chambers 13 and 14, respectively. The labyrinths 16 and 17 are gaps between the front train 6a and the gear trains 10a and 10b disposed in the rear chamber 7a and various support portions 3a extending from the inner wall of the transmission case 3. Is formed by. However, the labyrinths 16 and 17 may be separately formed in the transmission case.

  The breather chamber 13 is connected to the breather chambers 13 and 14 by the partition wall 8 sandwiched between the breather chambers 13 and 14 and above the breather inlets 13a and 14a on the inner peripheral surface side of the transmission case 3. A passage 18 is formed, one end of the breather passage 19 is communicated with the center of the breather communication passage 18 in the axial direction, and the other end is exposed to the outer periphery of the transmission case 3 and connected to one end of the breather hose 20. The breather communication path 18 is disposed substantially parallel to the drive shaft 5. Therefore, when the automatic transmission 1 is inclined downward at the rear, the breather communication path 18 is slightly inclined rearward. The other end of the breather hose 20 described above communicates with, for example, the air cleaner side.

  Stopper rings 21a and 21b are mounted on the inner periphery of the breather communication passage 18 at positions close to both breather chambers 13 and 14, respectively. Further, a ball valve 22 serving as a switching valve for switching the flow path is inserted between the stopper rings 21 a and 21 b of the breather communication path 18. As shown in FIG. 3, the breather communication path 18 is formed by press-fitting a metal pipe into the partition wall 8, for example. Stopper rings 21a and 21b are mounted inside the metal vibrator, and a plurality of holes 18a communicating with the breather passage 19 are formed in the center in the longitudinal direction. In this case, the breather communication path 18 may be directly formed in the partition wall 8.

  The stopper rings 21a and 21b are O-rings, and the ball valve 22 has a certain mass such as a metal ball and is movably inserted into the stopper rings 21a and 21b in the breather communication passage 18. . As will be described later, the ball valve 22 abuts against the stopper ring 21a or 21b on the side where the oil level is increased and the oil level rises, thereby blocking the breather chamber 13 or 14 from the breather passage 19.

  Next, the operation of the present embodiment having such a configuration will be described. When the rotational force of the engine is transmitted to the automatic transmission 1, the front chamber 6a provided in the front case 6 and the rear case 7 of the transmission case 3 via the torque converter in the torque converter case 2 and the rear The gear trains 10a and 10b rotate through the drive shaft 5 inserted through the chamber 7a, and the oil pump is driven.

  When the oil pump is driven, the oil stored in the oil reservoir 6b of the front chamber 6a is sucked up through the oil strainer 11, is pressurized, and is used as the operating hydraulic pressure of a transmission control device (not shown). These are supplied to lubrication required parts such as the gear trains 10a and 10b, and are lubricated and cooled. The oil used for the shift control and lubrication is returned to the oil reservoirs 6b and 7b formed at the bottoms of the front chamber 6a and the rear chamber 7a and circulated.

  In the front chamber 6a and the rear chamber 7a, oil mist stirred by rotation of the gear trains 10a, 10b, etc. is suspended and stagnated. When the temperature of the front chamber 6a and the rear chamber 7a rises and the internal pressure increases, the gas (breather gas) staying in both the chambers 6a and 7a flows through the labyrinths 16 and 17 to the breather device 12 side, and this breather device Through the breather hose 20 connected to 12, the air is released to the air cleaner (not shown) side to adjust the internal pressure. At that time, most of the oil mist contained in the breather gas is separated when passing through the labyrinths 16 and 17 and dropped into the two chambers 6a and 7a.

  Hereinafter, operation | movement of the breather apparatus 12 is demonstrated according to a driving | running | working condition.

[Cruising on flat road]
In cruise traveling on a flat road, the breather communication path 18 of the breather device 12 is inclined downward at the rear, so that the ball valve 22 rolls backward by its own weight as shown in FIG. The rear ring side breather chamber 14 and the breather communication passage 18 are blocked by lightly contacting the stopper ring 21b.

  As a result, the breather communication passage 18 is released to the front chamber side breather chamber 13, and the breather gas in the front chamber 6 a flows into the breather chamber 13, passes through the breather communication passage 18, the breather passage 19, and the breather hose 20. (Not shown). In this case, the breather gas in the rear chamber 7a flows into the front chamber 6a through a gap of a bearing 9 that rotatably supports the drive shaft 5 by the partition wall 8. Accordingly, the air pressures in the front chamber 6a and the rear chamber 7a are maintained in substantially the same state.

[Acceleration running, uphill driving]
When the vehicle accelerates, as shown in FIG. 6, the ball valve 22 moves to the rear chamber side breather chamber 14 side, abuts against the stopper ring 21b, and the rear chamber side breather chamber 14, the breather communication passage 18, and the like. Block between. As a result, the breather passage 19 and the front chamber side breather chamber 13 communicate with each other via the breather communication passage 18.

  On the other hand, during acceleration traveling, the oil stored in the oil reservoir 6b of the front chamber 6a flows into the rear chamber 7a side through the oil circulation hole 8a provided in the partition wall 8. Therefore, the amount of oil in the front chamber 6a is reduced, the oil level is lowered, the oil is biased toward the rear chamber 7a, and the oil level is raised.

  Therefore, in the front chamber 6a, the amount of oil mist stirred by the rotation of the gear train 10a decreases. Accordingly, the oil mist contained in the breather gas flowing into the front chamber side breather chamber 13 through the labyrinth 16 together with the breather gas is greatly suppressed, and most of the oil mist is separated and dropped in the breather chamber 13. It is possible to prevent the oil mist from being ejected from the breather passage 19 toward the air cleaner (not shown).

  Note that, when traveling on an uphill road, the front part of the vehicle body is inclined upward, so that the oil in the ball valve 22 and the transmission case 3 operates in the same manner as in the above-described accelerated traveling, so that the same effects as in the accelerated traveling are obtained. be able to.

[Decelerated travel, downhill travel]
When the vehicle decelerates, as shown in FIG. 7, the ball valve 22 moves to the front chamber side breather chamber 13 side and is pressed against the stopper ring 21a, so that the front chamber side breather chamber 13 and the breather communication path 18 are moved. Is interrupted. As a result, the breather passage 19 and the rear chamber side breather chamber 14 are communicated with each other via the breather communication passage 18.

  On the other hand, when traveling at a reduced speed, the oil stored in the oil reservoir 7b of the rear chamber 7a passes through the oil circulation hole 8a provided in the partition wall 8 and flows into the front chamber 6a. The oil level decreases, the oil is biased toward the front chamber 6a, and the oil level rises. Therefore, in the rear chamber 7a, the oil mist stirred by the rotation of the gear train 10a is reduced.

  As a result, the oil mist contained in the breather gas flowing into the rear chamber breather chamber 14 through the labyrinth 17 together with the breather gas is reduced. Accordingly, the oil mist contained in the breather gas flowing into the rear chamber side breather chamber 14 through the labyrinth 17 together with the breather gas is greatly suppressed, and most of the oil mist is separated and dropped in the breather chamber 14. It is possible to prevent the oil mist from being ejected from the breather passage 19 toward the air cleaner (not shown).

  In downhill traveling, the front part of the vehicle body is inclined downward, so that the oil in the ball valve 22 and the transmission case 3 operates in the same manner as the above-described decelerating travel. Can do.

  The present invention is not limited to the above-described embodiment. For example, the front chamber side breather chamber 13 is disposed at the front portion of the front chamber 6a, and the rear chamber side breather chamber 14 is disposed at the rear portion of the rear chamber 7a. The inflow of oil mist may be further suppressed. Moreover, the front part of the breather communication path 18 may be inclined downward. By tilting the front portion of the breather communication passage 18 downward, the front chamber side breather chamber 13 is always shut off during cruise traveling on a flat ground, and the breather gas staying in the rear chamber 7a is released outside the transmission case 3.

  The applied vehicle may be a hybrid vehicle having an engine and a motor as drive sources. In this case, a motor generator is arranged in the rear chamber 7a instead of the gear train 10b. Furthermore, the self-answer transmission 1 may be a horizontal type. Further, the transmission is not limited to an automatic transmission and may be a manual transmission.

1 ... Automatic transmission,
3. Transmission case,
5 ... drive shaft,
6 ... the front case,
6a ... Front room,
7 ... Rear case,
7a ... rear room,
8 ... partition wall,
8a ... hole for oil circulation,
10a, 10b gear train,
12 ... breather device,
13 ... Breather room in front room,
14… Breaser room on the back room side,
18… Breeza passage,
19 ... Breeza passage,
21a, 21b Stopper ring,
22 ... Ball valve

Claims (3)

At least two divided cases formed by dividing a transmission case mounted on a vehicle by a plane perpendicular to a drive shaft disposed in the transmission case;
A partition wall partitioning each of the divided cases;
An oil circulation hole provided at a position lower than the oil surface of the partition wall and communicating between the adjacent divided cases;
A breather chamber having an inlet through which the breather gas in each split case flows;
A breather passage for escaping the breather gas flowing into the breather chamber out of the transmission case;
The breather chamber is provided in the upper part of each of the divided cases;
Each breather chamber provided in each divided case adjacent via the partition wall is communicated via a breather communication path,
The breather communication passage communicates with the breather passage;
A breather for a transmission, wherein a switching valve for selectively shutting off one of the breather chambers and the breather passage according to acceleration / deceleration traveling of the vehicle or its own weight is interposed in the breather communication passage. apparatus. The switching valve is a ball valve that freely moves in the breather communication path,
2. A breather device for a transmission according to claim 1, wherein a stopper ring is provided on the side of each breather chamber of the breather communication passage so as to hook the ball valve and block the flow path. The breather device for a transmission according to claim 1 or 2, wherein the breather communication passage is inclined from one of the breather chambers to the other.

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